User can't login because of "Invalid password format or unknown hashing algorithm."-Django

I'm learning Django and tried to write my own custom user model. I'm not using DRF and serializers and stuffs I have no idea about :) I am using createView to create users but I can't login because "Invalid password." I checked the user's password in admin and the user's password is "Invalid password format or unknown hashing algorithm." .

here are the codes: Custome User and User Manager in models

class UserManager(UserManager):
    def create_user(self, username, email, password, **extra_fields):
        if not email:
            raise ValueError('User must have email')
        if not username:
            raise ValueError('User must have username')
        user = User.objects.create_user(
            username=username,
            email=self.normalize_email(email),
            )
        
        user.set_password(password)
        user.save()
        return user

    def create_superuser(self, username, email, password, **extra_fields) :
        user = self.create_user(username, email, password)
        user.is_staff = True
        user.is_superuser = True
        user.is_admin = True
        user.is_active = True
        user.save()
        return user



class User(AbstractBaseUser):
    username = models.CharField(unique=True, max_length=200)
    email = models.EmailField(unique=True)

    is_superuser = models.BooleanField(default=False)
    is_active = models.BooleanField(default=False)
    is_admin = models.BooleanField(default=False)
    is_staff = models.BooleanField(default=False)

    date_joined = models.DateTimeField(default=timezone.now)
    modified_at = models.DateTimeField(auto_now=True)

    objects = UserManager()
    REQUIRED_FIELDS = ["username","email", "password"]
    USERNAME_FIELD = "username"
    def __str__(self):
        return self.email

    def has_perm(self, perm, object=None):
        "Does the user have a specific permission?"
        return self.is_admin

    def has_module_perms(self, app_label):
        "Does the user have permissions to view the app `app_label`?"
        # Simplest possible answer: Yes, always
        return True

SignUp and login in views

class SignUp(CreateView):
    model = User
    form_class = CUForm
    
    success_url = reverse_lazy('index')


def login(request):
    if request.user.is_authenticated:
        messages.warning(request, 'You are already logged in.')
        return redirect('/list')
    elif request.method == 'POST':
        username = request.POST['username']
        password = request.POST['password']

        user = auth.authenticate(username=username, password=password)
        if user is not None:
            auth.login(request, user)
            return redirect('/list')
        else:
            try:
                user = User.objects.get(username=username)
                messages.error(request, 'Invalid password.')
            except:
                messages.error(request, 'Invalid username ')

            return redirect('login')
    return render(request, 'accounts/login.html')

and forms.py

class CUForm(forms.ModelForm):
    username = forms.CharField(max_length=200)
    email = forms.EmailField(widget=forms.EmailInput())
    password = forms.CharField(widget=forms.PasswordInput())
    confirm_password = forms.CharField(widget=forms.PasswordInput())

    class Meta:
        model = User
        fields = ['email','username','password',]
    def clean(self):
        cleaned_data = super(CUForm, self).clean()
        password = cleaned_data.get('password')
        confirm_password = cleaned_data.get('confirm_password')
        if password != confirm_password:
            raise forms.ValidationError('Password does not match.')

and admin

class CostumeUserAdmin(UserAdmin):
    list_display = ('email', 'username', 'is_active', 'is_admin')
    filter_horizontal = ()
    list_filter = ('is_staff',)
    fieldsets = ()

admin.site.register(User, CostumeUserAdmin)

I have read some of the solutions and I changed

 user = self.model(
           username=username,
           email=self.normalize_email(email)
             )

to

user = User.objects.create_user(
            username=username,
            email=self.normalize_email(email),
            )

Alrigh I have fixed the "Invalid password format or unknown hashing algorithm." issue by adding this to my createView:

def form_valid(self, form):
    user = form.save(commit=False)
    password = self.request.POST['password']
    user.set_password(password)
    user.save()
    return super().form_valid(form)

and the password now saves correctly, not sure why but it does. And then I realized I didn't add AUTH_USER_MODEL = 'accounts.User' in my setting.py! I still don't know why I need to use set_password in form_valid even tho I used it in UseManager but now It works!